The goal of this research is to determine the efficacy and safety of Traditional Chinese Acupuncture (TCA) in patients with osteoarthritis of the knee. A three arm randomized controlled trial (RCT) using sham TCA, true TCA, and an education/attention comparison group with a total sample of 525 is proposed. Primary hypothesis to be tested is that patients randomized to true TCA will have significantly more improvement in pain and function as measured by the Womac Pain & Function Scales and patient global assessments than patients randomized to the sham acupuncture and education/attention control groups.